Refugium section is going to include the rest of sand that I have, some live rock pieces that I won't use in display, 1 blue tux sea urchin, emerald crabs, trocus, nerites, and narssissus. Mainly using it for chaeto growth, been reading some on Xenia and it's nutrient transporting as well so might include a back wall of Xenia. I have an hob refugium that I'll put on far left where the dt tank dumps in for the time being.